1. Field of the Invention
The invention relates to a device and a method for aligning sheets prior to transferring the sheets to a sheet processing machine.
The published German Patent Document DE 198 22 307 A1 discloses a device of the type mentioned herein which has a sheet entrainer formed by a transporting roller and serving for aiding in a displacement, over a fixed distance transversely to a sheet travel direction, of a sheet having a leading edge thereof abutting front lays, until a lateral edge of the sheet strikes against side lays. It has been found that in-register alignment of the sheets cannot be ensured in all cases because the sheet can twist as it strikes against the side lays, thereby forming an aligning-error angle. It is also disadvantageous that the outlay for controlling the movement of the entrainer in order to displace the sheet over a precise distance is very high, and the construction of the device involves great outlay.